Since upgrading to Logic Pro 11 I constantly get an error saying "An Audio Unit plug-in reported a problem which might cause the system to become unstable. Please quit and restart Logic Pro."

Solved... mostly.

This worked as you said it would, thank you.

Of course, it cannot fix the underlying issue of the plug-in that was made incompatible with Logic Pro (which was Bias FX 2 by Positive Grid for anyone curious.) But, using your method I was able to hit 'X' to bring up the mixer, click 'recover' which gave me just enough time for a SINGLE well-placed click before the error message would come back up. I had quite a few tracks with this plug-in on it and each and every one had to have the problem plug-in COMPLETELY GONE from the track stack, not just 'turned off.' That means anyone having this issue needs to go to where the plug-in drop down menu is and set it to 'no instrument,' while having to constantly click 'recover' in-between each click. I fear that those on slower systems may have even less time than I did in-between clicks as even on an M1 system it bogged Logic down badly in this tedious process.

Eventually though, when Bias FX 2 was purged from every track the error stopped coming up. So now I have absolutely no guitar processing on the project, but at least it's not a complete loss.

Thanks again.

Also, boo to Positive Grid for their expensive software not being compatible with one of the most common DAWs in the land, and boo to Apple who designed such a terrible process for malfunctioning plug-ins.

Solved... mostly.

This worked as you said it would, thank you.

Of course, it cannot fix the underlying issue of the plug-in that was made incompatible with Logic Pro (which was Bias FX 2 by Positive Grid for anyone curious.) But, using your method I was able to hit 'X' to bring up the mixer, click 'recover' which gave me just enough time for a SINGLE well-placed click before the error message would come back up. I had quite a few tracks with this plug-in on it and each and every one had to have the problem plug-in COMPLETELY GONE from the track stack, not just 'turned off.' That means anyone having this issue needs to go to where the plug-in drop down menu is and set it to 'no instrument,' while having to constantly click 'recover' in-between each click. I fear that those on slower systems may have even less time than I did in-between clicks as even on an M1 system it bogged Logic down badly in this tedious process.

Eventually though, when Bias FX 2 was purged from every track the error stopped coming up. So now I have absolutely no guitar processing on the project, but at least it's not a complete loss.

Thanks again.

Also, boo to Positive Grid for their expensive software not being compatible with one of the most common DAWs in the land, and boo to Apple who designed such a terrible process for malfunctioning plug-ins.